The death of Margaret Thatcher demonstrates the double standards among sections of the left. In Britain, Thatcher-haters are running an online campaign to push the song Ding Dong! The Witch Is Dead to the top of the charts. Apparently it's acceptable to brand Britain's first female prime minister, and its longest-serving leader in the 20th century, as a ''witch''.

In Australia the word usage has been even more offensive. Last Wednesday The Age ran an opinion piece by Michael Lynch. He wrote that ''for everyone who painted her [Thatcher] as a dynamic moderniser … there was another who regarded her as a heartless bitch''. Lynch made it clear that he was in the latter category.

So it seems it's OK to use the ''b'' word with respect to the conservative Thatcher. This would be unacceptable – and properly so – if such a term of abuse was used against a leading social democratic politician like Julia Gillard.

And then there is the act of celebration. When Q&A presenter Tony Jones announced on the program last week that Thatcher had died, visiting academic Brooke Magnanti immediately interjected: ''And me with no champagne''. It is understandable why the likes of Magnanti want to criticise Thatcher and her legacy. However, it is scarcely a triumph when a political enemy dies at the advanced age of 87.

Thatcher's death has ushered in a moment of fool-headedness among the left. Eco-catastrophists, who warn about global warming, have condemned Thatcher for presiding over the closing of dirty and inefficient coal mines in northern England and Wales in the 1980s. Yet it was these closures which made it possible for Britain to meet its emission targets under the Kyoto agreement.

Then there are the leftists who have depicted Thatcher as a war-monger because in 1982 she refused to accept the invasion of the Falkland Islands, which is British territory, by Argentina. This despite the fact that, at the time, Argentina was ruled by a corrupt right-wing junta.

Glenda Jackson, former actor and now left-wing Labour parliamentarian, used the time allocated in the House of Commons for tributes to Thatcher to declare: ''The first prime minister denoted by female gender. OK. But a woman? Not on my terms.'' So, according to Jackson, Thatcher was not a woman because she did not fit a leftist feminist stereotype.

Thatcher was admired by many because she stood up to the communist totalitarian dictators in the Soviet Union, to General Galtieri in Argentina, to Colonel Gaddafi in Libya, to the violence-prone thugs who ran the Provisional Irish Republican Army at the time and job-destroying militant union leaders.

However, Thatcher was not as dynamic as many of her supporters and opponents suggested. As Financial Times columnist Martin Wolf commented, Thatcher ''was a pragmatic politician who showed little interest in embarking on politically suicidal attempts to demolish pillars of the welfare state''. During Thatcher's time, public spending as a percentage of gross domestic product never fell below 39 per cent.

The first volume of Charles Moore's authorised biography of Thatcher will be published soon. Writing in the Daily Telegraph last week, Moore acknowledged that Thatcher got ''many things'' wrong – like all great leaders. But he added that she left an important, and positive, mark on the British and international stages.

Foreign Affairs Minister Bob Carr has attained international attention for his claim, on Lateline last Tuesday, that Thatcher had been ''unabashedly racist'' in private comments made to him about Asian immigration. The reported conversation took place in 1999, long after Thatcher's resignation in 1990.

I met Thatcher during her visit to Australia in November 1995. She performed well at a public luncheon address but at a private dinner the following evening Thatcher seemed to struggle somewhat. As John Campbell makes clear in his balanced biography Margaret Thatcher (Vintage, 2009), Thatcher suffered her first stroke in 1994 and thereafter suffered short-term memory loss. He wrote that by the mid-1990s she was ''simply ranting'' at times.

On Insiders last Sunday, David Marr referred to Thatcher as a ''notorious racist''. There is no evidence for this. She was a strong supporter of the rights of Asians in Hong Kong and of Muslim Bosnians in the former Yugoslavia. Thatcher may have been right or wrong on the efficacy of imposing sanctions on South Africa during the apartheid regime. But she worked hard privately to get Nelson Mandela out of prison and he visited Thatcher at 10 Downing Street to express thanks for her efforts on his behalf.

Senator Carr has always admired parts of Thatcher's agenda. Thatcher should be judged when she was at the height of her powers – not after she was diminished by debilitating illnesses in retirement.